Manufacture of dyes containing chromium and the resulting product



P tented Au 29. 1933 MANUFACTURE OF PATENT or FlCE I mms CONTAINING CHROMIUM AND THE RESULTING PROD UCT ' Ernestv Albert Sack, Neullly-sur-Seine, France, assignor to Compagne Nationale de Matieres Colorantes & Manufactures dc 'Produits Chimiques du Nord. Reunie s, Etablissements. Kuhlmann, Paris, France, a corporation o1 France Na Drawing. Application June 18, 1930, Serial 462,142, and in France November 13, 3 f

3 Claims; (c1. act-12) In my application for Patent Serial No. 462,143 I have described a process oi. manufacture of chromium compounds of orthoj-hydroxyazo dyestuffs by heating the latter with asolution of a chromium salt of a mineral acid (chromium sulphate for example) in the presence or absence of free mineral'acid, and more particularly of sulphuric acid. I

According to the present invention chromed azo 0 dyes derived from ami'no-naphthols and pyrawater, to which is added 8 kgs. of sulphuricacid zolones and howsoever chromed are heated with dilute sulphuric acid andwith or without added pressure. By this process some chromium is eliminated and new chromed'dyes' are produced whose shade is quite different fromithatof the initial chromed dye. n

The following is an example illustrating the invention but without imposing limitations, The ,red blue chromium compound,- obtained in the absence of mineral acid, starting with 42.5 kgs. of the azo dye prepared by coupling the diazo compound of l-amino-2-hydroxynaphthalene-4- sulphonic acid with 1-phenyl-3-methyl-5-pyrazolone, is heated ina sealed autoclave under pressure to 120" C. for 20 hours with 400 litres of of 66 B.

On completion of the reaction an elimination of chromium is noted in the form of sulphate. The new chromium compound transformed into sodium salt after filtration and washing, colors woolfunder acid bath a brightrose, while the initial chromium compound used for dyeing in the same conditions gives a dull bluish red shade.

The new chromium compound is identical with that described in Example 1 of application Serial No. 462,143.

What I claim is:-

1. The manufacture of chromed dyes from redblue chromium compounds of ortho-hydroxyazo dyes derived from pyrazolones, which consists in subjecting the same to the action of dilute sulphuric acid. 2. The manufacture of chromed dyes as claimed inclaim' 1, in which the reaction is effected in a sealed container under heat and pressure.

3. The manufacture of chromed dyes from redblue chromium compounds of ortho -hydroxyazo dyes derived from pyrazolones and ortho-amino-- hydroxy-naphthalene sulphonic acids, which consists in subjecting the same to the action of dilute sulphuric acid.

4. The manufacture of chromeddyes from redblue chromium compounds of ortho-hydroxyazo dyes derived from 1-phenyl-3-methyl-5-pyrazolone and 1 amin0-2hydroxy-naphthalene-isulphonic acid; whichconsists in subjecting the same to the action of dilute sulphuric acid.

'phuric acid of a part of the chromium from redblue chromed ortho-hydroxyazo dyes derived from pyrazolones.

7. The manufacture of chromed dyes as claimed in claim 4 in which the reaction is ef- Iected under pressure at a temperature of about 8. The dyes of changed shade obtained by elimination by sulphuric acid of a part of the chromium fromazo dyes, derived from orthoaminonaphtols and from pyrazolones. ERNEST ALBERTSACK. 

